1452351 - box shadow rendering issue

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P1)

Description

[DivineGod]

Attachment: reduced test case.

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:61.0) Gecko/20100101 Firefox/61.0
Build ID: 20180406220121

Steps to reproduce:

Enabled web render in about:config (gfx.webrender.all true)
Restarted Firefox Nightly
Navigated to imdb.com


Actual results:

Saw a rendering issue along the left side of the page where a box shadow is meant to be
Scrolling makes the rendering issue disappear until reaching the bottom of the page


Expected results:

There should be a box shadow and not a rendering bug.

Comment 1

[DivineGod]

Attachment: Rendering issue on imdb.com

This image shows the rendering issue when scrolled to the top of the page

Comment 2

[DivineGod]

I've also created a codepen for this reduced testcase and in this case the only point it triggers is in full page mode: https://s.codepen.io/DivineGod/fullpage/geQLqa or https://codepen.io/DivineGod/full/geQLqa and not in normal editing mode for the codepen: https://codepen.io/DivineGod/pen/geQLqa

Comment 3

[Milan Sreckovic [:milan] (needinfo for best results)]

Mac only?

Comment 4

[Kartikaya Gupta (email:[e-mail])]

I only see this on Mac, and it's a regression from https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=5110a382f6a073a9fa220936442125c961bc57af&tochange=8a988d1a6f23f900b90c7843e2c61db14a57e56c which means it's from one of these changes in upstream WR:

*   5cb71f0f Auto merge of #2499 - kvark:revert-fix, r=staktrace
|\
| * 9b069b7b Revert "textureSize() workaround for Angle/NV" for (somehow) causing text rendering issues on OSX.
* |   ce9c75b5 Auto merge of #2496 - jrmuizel:div, r=kvark
|\ \
| |/
|/|
| * fa1090c4 Do division and mod on unsigned integers
* |   7e459e81 Auto merge of #2497 - glennw:bi-opt, r=kvark
|\ \
| |/
|/|
| * 584459c6 Small optimization for the brush_image shader.
|/
* f3af2632 Auto merge of #2487 - glennw:bs-clip15, r=kvark
* 18cc8adb Handle minimal shadow rects with fractional offsets / sizes.
* 81f55acd Switch box-shadows to be a clip source instead of a picture.

Of these changesets, 81f55acd seems the most likely since it refers to box-shadows.

Also, interestingly, the issue goes away if I have the TreeStyleTabs sidebar open. Other sidebars (e.g. bookmarks/history) also affect the presence of the issue, but depending on what I'm hovering over on the sidebar.

Comment 5

[Glenn Watson [:gw]]

Will be fixed when https://github.com/servo/webrender/pull/2799 lands in Gecko.

Comment 6

[Kartikaya Gupta (email:[e-mail])]

I still see this issue in the try push at https://treeherder.mozilla.org/#/jobs?repo=try&revision=6caa069341563b07bd4570ef6fb6add083061072 which includes servo/webrender#2799

Comment 7

[Glenn Watson [:gw]]

Looks like I commented in the wrong bug. The fix in #2799 was for https://bugzilla.mozilla.org/show_bug.cgi?id=1458661, sorry!

Comment 8

[Kartikaya Gupta (email:[e-mail])]

Mac only, dropping it off the nightly blocker list.

Comment 9

[Patrick Walton (:pcwalton)]

Can't reproduce anymore on Mac. Should we close?

Comment 10

[Darkspirit]

(In reply to Patrick Walton (:pcwalton) from comment #9)
> Can't reproduce anymore on Mac. Should we close?

Are you able to reproduce bug 1490883?

Comment 11

[Darkspirit]

On the other hand, the worst part of this shadow regresson might have already been fixed for MacOS: bug 1472455 comment 10

Comment 12

[Patrick Walton (:pcwalton)]

(In reply to Jan Andre Ikenmeyer [:darkspirit] from comment #10)
> (In reply to Patrick Walton (:pcwalton) from comment #9)
> > Can't reproduce anymore on Mac. Should we close?
> 
> Are you able to reproduce bug 1490883?

Commented over there, but I can't reproduce that bug. I'm on Mac.

Comment 13

[lindemann.ethan]

I also am unable to reproduce this bug.

Comment 14

[Jeff Muizelaar [:jrmuizel]]

Looks fixed. Please reopen if not.